This is a competing continuation application to renew the Illinois Research Training Program in Environmental Toxicology. The Program, established in 2000 educates pre-and post-doctoral trainees in reproductive, developmental and endocrine toxicology. The need for training in these aspects of toxicology is every bit as urgent today as it was 15 years ago when the Training Program was first conceived. Chemicals that act as endocrine disruptors continue to dominate environmental health concerns. The Program unites two long- standing areas of research excellence on the University of Illinois campus-environmental toxicology and reproductive biology. Nineteen faculty members from eight departments in four colleges will serve as preceptors, making this a truly interdisciplinary training program. Eleven, including the Program director and associate director, have been affiliated with the Training Program since its early days, providing long-term stability and continuity. Four joined around the time of our last competitive renewal and five joined within the past year. The recent addition of new preceptors has allowed us to expand training opportunities into important new research areas including environmental obesogens, environmental impacts on the microbiome, environmental impacts on neuro-immune function, and interactions of environmental exposures with drugs of abuse. The preceptors are well funded, collaborate extensively, and have a wealth of experience mentoring students and post-docs. Together they currently have over 40 federally funded research grants totaling more than 8 million dollars/year direct costs, and 27 grants from other sources totaling over 2 million dollars/year direct costs. Collaborations among labs working at the molecular, cellular, whole animal and human health levels provide trainees with the unique opportunity to directly observe and participate in translational research. Selection of the 4 pre- and 3 post-doctoral trainees thi Program supports is based on academic success, strength of the proposed research, relevance of the research to Program goals, and commitment to toxicology. Trainees are appointed for 2 years. The Program offers a broad range of graduate level courses in toxicology. In addition to fulfilling departmental requirements, all pre-doctoral trainees take basic toxicology, systems toxicology, and at least one other advanced toxicology course. Post-doctoral trainees conduct independent research. All pre- and post-doctoral trainees attend weekly toxicology research seminars, a monthly toxicology journal club, and a course on research ethics in toxicology, coordinated by the director and team taught by the preceptors. Trainees also attend career development workshops and take a grant writing class. They are required to present their research in the toxicology seminar and strongly encouraged to attend international meetings to present their work. Recruitment of trainees from under-represented groups is a high priority and strong efforts to diversify the Training Program will continue in the next funding period. Trainees are expected to pursue toxicology-related careers in academia, government or industry.